Optical Waveguide Lightmode Spectroscopy (OWLS) Evanescent Field Detection of Surface Processes on Transparent, Metal-Oxide-Type of Surfaces

Technique:

Figure 1: Schematics of the OWLS working principle: a grating couples the laser into the waveguide at a well-defined angle, and the incoupled light is captured by the detector. A flow-through cuvette serves for the controlled exchange of analytes.

The OWLS technique uses the evanescent field of a He-Ne laser which is coupled into a planar waveguide via an optical grating (see Figure 1). This incoupling only occurs at two distinct incident angles according to the mode equations. Continuously measuring the shift of these incoupling angles allows the direct online monitoring of the adsorption of macromolecules above the grating without the need for any labeling procedure. The method is highly sensitive (i.e., ~1ng/cm²) up to a distance of a few hundred nanometers above the surface of the waveguide. Furthermore, a measurement time resolution of 3 seconds permits an in situ, real-time study of adsorption kinetics.

Applications:

• Protein adsorption kinetics on different metal-oxide surfaces.
• Adsorption of polymeric adlayers and test for their protein resistant behaviour.
• Measuring the formation and the performance of molecular docking sites.
• Antibody-antigen interactions.
• Effect of applied surface potential on polyelectrolyte adsorption.

Contact:

• Janos Vörös
• Marcus Textor

Partners:

• Microvacuum Ltd.

References:

• Electrochemical Dissolution of Polyelectrolyte Multilayers for the Controlled Delivery of Drugs
  F. Boulmedais, C.S. Tang, B. Keller, J. Vörös; Advanced Functional Materials, submitted August 2004
• Immobilization of the enzyme β-lactamase on biotin-derivatized poly(L-lysine)-g-poly(ethylene glycol) coated sensor chips: a study on oriented attachment and surface activity by enzyme kinetics and in situ optical sensing
  G.L. Zhen, E. Zobeley, V. Eggli , J. Vörös, P. Zammaretti , R. Glockshuber, M. Textor; Langmuir, in press
• Protein Resistance of Titanium Oxide Surfaces Modified by Biologically Inspired mPEG-DOPA
  J. L. Dalsin, S. Tosatti, J. Vörös, M. Textor, P. B. Messersmith; Langmuir, submitted in June 2004
• The Density and Refractive Index of Adsorbing Protein Layers
  J. Vörös; Biophysical Journal, 87:1-9, 2004.
• Poly(L-lysine) -graft-poly(ethylene glycol) assembled monolayers on niobium oxide surfaces: a quantitative study of the influence of polymer interfacial architecture on resistance to protein adsorption by ToF-SIMS and in situ OWLS
  S. Pasche, S.M. De Paul, J. Vörös, N.D. Spencer and M. Textor; Langmuir, 19(22): 9216-9225, 2003.
• Electrochemical Optical Waveguide Lightmode Spectroscopy (EC–OWLS): A Pilot Study Using Evanescent-Field Optical Sensing Under Voltage Control to Monitor Polycationic Polymer Adsorption onto Indium Tin Oxide (ITO) Coated Waveguides
  J.P. Bearinger, J. Vörös, J.A. Hubbell and M. Textor,
  Biotechnology and Bioengineering, 82 (4): 465-473, 2003.
• Boundary lubrication of oxide surfaces by Poly(L-lysine)-g-poly(ethylene glycol) (PLL-g-PEG) in aqueous media
  S. Lee, M. Müller, M. Ratoi-Salagean, J. Vörös, S. Pasche, S.M. DePaul, H.A. Spikes, M. Textor, N.D. Spencer, Tribology Letters 15(3): 231-239, 2003.
• Optical Grating Coupler Biosensors (Review Article)
  J. Vörös, J.J. Ramsden, G. Csucs, I. Szendrö, M. Textor and N.D. Spencer, Biomaterials, 23 (17): 3699-3710, 2002.
• Biotin-Derivatized Poly(L-lysine))-g-Poly(ethylene glycol): A Novel Polymeric Interface for Bioaffinity Sensing
  N.P. Huang, J. Vörös, S. M. DePaul, M. Textor, N. D. Spencer, Langmuir, 18(1): 220-230, 2002.
• A Comparative Study of Quantitative Protein Adsorption on Titanium Oxide Surfaces Using in situ Ellipsometry, Optical Waveguide Lightmode Spectroscopy, and Quartz Crystal Microbalance Techniques
  F. Höök, J. Vörös, M. Rodahl, R. Kurrat, P. Böni, J.J. Ramsden, M. Textor, N.D. Spencer, P. Tengvall, J. Gold and B. Kasemo, Colloids and Surfaces B, 24(2): 155-170, 2002.
• Effect of Patterns and Inhomogeneities on the Surface of the Waveguide in Optical Waveguide Lightmode Spectroscopy Applications
  R. Horváth, J. Vörös, R. Graf, Gy. Fricsovszky, M. Textor, L.R. Lindvold, N. D. Spencer and E. Papp,
  J. Appl. Phys. B., 72(4): 441-447, 2001.
• Poly(L-lysine)-g-poly(ethylene glycol) Layers on Metal Oxide Surfaces: Surface-analytical Characterization and Resistance to Serum and Fibrinogen Adsorption
  N. P. Huang, R. Michel, J. Vörös, M. Textor, R. Hofer, A. Rossi, D. L. Elbert, J. A. Hubbell, N. D. Spencer, Langmuir, 17(2): 489-498, 2001.
• Influence of Polymer Surface Chemistry on Frictional Properties under Protein-lubrication Conditions: Implications for Hip-implant Design
  M. R. Widmer, M. Heuberger, J. Vörös, N. D.Spencer,
  Tribology Letters, 10(1-2): 111-115, 2001.
• Protein Resistance of Self-assembled Poly(l-lysine)-g-poly(ethylene glycol) Layers on Oxide Surfaces Measured by the Optical Waveguide Technique
  G. L. Kenausis, J. Vörös, D.L. Elbert, M. Textor, J. Hubbell, N.D. Spencer,
  J. Phys. Chem.B, 104(14): 3298-3309, 2000.
• Feasibility Study of an Online Toxicological Sensor Based on the Optical Waveguide Technique
  J. Vörös, R. Graf, G. Kenausis, M. Textor, A. Bruinink, E. Wintermantel, N. D. Spencer,
  Biosensors and Bioelectronics, 15(9-10): 423-429, 2000.
• Phosphorylcholine Containing Polyurethanes for the Control of Protein Adsorption and Cell Attachment via Photoimmobilised Laminin Oligopeptides
  L. Ruiz, E. Fine, J. Vörös, S.A. Makohliso, D. Léonard, D.S. Johnston, M. Textor, H.J. Mathieu, Journal of Biomaterials Science. Polymer Edition, 10(9): 931-955, 1999.